Apparatus for producing cap screws and the like



Aug. 28, 1928. 1,682,520

V. HUSVAR APPARATUS FOR PRODUCING CAP SCREWS AND. THE LIKE Filed Jan. 5. 1922 2 Sheets-Sheet 1 awuentoz E1513 award W450 V91 flu Aug. 28, 1928. 1,682,520

V. HUSVAR APPARATUS FOR PRODUCING GAP SCREWS AND THE LIKE Filed Jan. 5. 1922 2 Sheets-Sheet 2 I mccxnumn\ I 12 jlzfy. Eryn.

avwwwtoz Patented Aug. 2a. 1928.

' UNITED sures PATENT 1,682,520 OFFICE.

vmcimr sewn, or warmumr, comm, assumes. 'ro scovna. mu-

racrunme 00., or wn'mumr, common-r, a oonromrrorr or commonmeasure :03 rnonucme car scmaws AND rm; LIKE.

Application filed January 5, 1882. Serial In. 687,116.

This invention relates to a method of and aliparatus for producing cap-screws or the l' e.

The usual commercial practice, in making cap-screws, has been to head u a cold rod to form a blank having a shan and a substantiall circular head. This blank is then place in. a milling machine and the facets which form the poly onal head of the finished product are ed, giving a smooth, machined surface demanded by the trade. This milling operation is expenslve and increases the cost of the screws.

It is the principal object of thepresent invention to of and means or producin cap-screws without milling the facets of e head With this general object in view the invention consists in the methods, combinations, details of construction, and arrangements of parts which will first be described in connection with the accom anying drawings and then more particular y pointed out.

In the drawing: 7 Fig. 1 is a view in vertical section of apparatus embodying the invention; igs. 2-5inclusive are sectional yiews (enlarged) through the die, showing the parts in diiferent progresive sitions;

. 6 is a front face new of the planishin ie removed;

ig. 7 is a rear face view of the cutting die removed; and

Figs. 8-11 are side views of the blank, in-' termediate blank, cut blank and finished product respectively. V

In carrying out the invention, blanks are formed in any suitable manner, as by headthe-cut or, shaved. of! waste metal forms a sort of i: which ispushed ahead until itr'eaches. topor bottom of the head mg up cold a rod of the desired" size. This step provides a blank with a circular head Fig. 8). To form the facets of'the head, e blank is subjected to the action of a polygonal die in such manner that the ex- "cess metal is removed by a one-way cut. That is to say starting at the top or bottom of the head, e die cuts acm the side of the head in one direction until the excess metal is cut through, as for example, from a cutting action working from both totp1 and bottom toward the center.

- 'As e die cuts away the excess metal,

provide an improved method bone, as appears in Fig.

(accordinglothe direction of cut) and is eventually removed. Fig. 9 illustrates this waste flange at the top of the head just prior to being severed. In carrying out the invention according to what is considered the best method, this waste flange, at the time it is severed from thehead, is positivelyheld or pinched. With this method, tearing of the metal on the facets is avoided and a clean cut or breakris obtained.

In carr g out the invention in its en- .tlrety, the facets of the head are planished, for example, by a planishing die, and preferablythis planishing operation 'is carried on under lubrication. This planishing eliminates any roughness left at the point where and as a result the facetspresent the smooth, clean demanded by the trade. Fig. 10 illustrates a blank after severance of. the head and planishing of the facets...

The blank may then be trimmed in any suitable manner to remove any roughness at the waste flange or web is eventually cut oil the juncture of the facets with the face of the head, in this instance, the to of the head. Fig. 11 shows-the trimmed iead.

It will be understood that to form a complete cap-screw, the shank V is suitably threaded. But for the purposesof the present invention the finished product is the cut,-

lanished and trimmed head, the threading assumed.

operation being Referring to the drawings, the invention includes a cutting die, a blank holder and means for causing relative movement between the die and the blank to cut the facets of the head with a onc-wa cut. In the-embodiment shown, a blank (Fig. 8) with a circular head 101 is forced througha stationary cutting die. To this end, as here shown, there is provided a cutting die 12, held in a die block 13 carried by a frame 14. The die 12 has 'a polygonal cutting 7, to cut the circular head into facets, thereby lllproducing a poly nal .head, the die here ustrated bemg.

exemplification the blank The invention includes means for holding the blank and in invqutiouto the best advantage, the ho ding is inserted the die shank first and the head is Man hexagonal head. In the present 7 through the; die as hereinafter deembodyin the ing on a bed means is so arranged as. to insure concentrieity between head and shank in the completed product. Although capable of various constructions, in that here illustrated as an example, a tubularholder 15 is carried by a tubular member 16 reci rocably mounted in a bushing 17 mounte in the frame. The tubular member 16 slides on a rod 18 sus ended b a bracket 19 from a tie rod 20. he hol er 15 has an internal bore designed to make a close fit with the shank 102 of the blank, thereby firmly holding the blank and preventing any substantial play or tilting of the blank during cutting. As a result the cut heads are uniformly concentric with the shanks.

Means is provided for moving the holder 15. Although capable of various constructions in that here illustrated, threaded onto tubular member 16 is a grooved collar 21 engaged by a yoked lever or rocker arm 22 mounted on a rock shaft 23. Shaft 23 being rocked by any suitable means, such as a cam and rocker arm, member 16 and the holder 15 reciprocate as later described. By moving the connector 21 along the threaded portion of tubular member 16, the stroke of the latter may be adjusted with respect to the die.

The blanks may be inserted in the holder in any suitable manner, it being understood that at this time the holder is advanced into the die in some such position as shown in Fig. 2. This insertion may be done by hand or it may be accomplished by feeding and positioning means in connection with the pushing means later described. Fig. 1 illustrates, as an example, a feeding and positioning means comprising a vertically reciprocatmg slide 25 operated by a l' 26, rocker arm 27 and suitably driven rock shaft 28. The slide 25 carries a spring gripper 29 for grasping theend of the shank in the manner shown in Fig. 1. The blanks are fed down a chute 30, and are carried to a position to be taken by the gripper 29. by a slide 31 operated by a rocker arm 32. The blanks being carried down by gripper 29 to a position opposite the die, are moved into the waiting older 15 by the advance of the pushing element about to be described.

The invention includes means for forcing the blank head through the die, and for pinching or grasping the shaved off flange of waste metal at the time the latter is severed from the head. This may be accomplished, for example, by a two part pushing element having such differential movement" that one part may'act as a pinching element at the end of the pushing stroke while the other part continues the pushing stroke. Although in the presentexem lification, reciprocat- I plate 33 1s a slide 34 having in its forward end aholder'35 for a hardened For thc purposes of forcing the capable of various. constructions,

block 36. The slide 34, is reciprocatcd, as here shown, by a double toggle 37, 38, actuated by a pitman 39 driven by a crank 40.

The diii'erential pusher, 1n the resent embodiment, comprises a pusher )ar 41 movable through a central bore in the pusher block 36. The forward end of pusher bar carries a springpressed, relatively movable )usher pin 42. The function of this pin 42 has to do with the ejectment of the blanks as hereinafter described. blank head through the die the pusher pin 42 may be considered as one with bar 41. Bar 41 is slidable in a bushing 43 in the slide 34 and is carried by a slide block 44, movable in a channel 45 formed in the main slide 34. To give the pusher bar 41 its differential movement, there is provided, in the present embodiment, a wedge or cam 46 movable between a roller 47 carried by the main slide 34 and a roller 48 carried by the supplemental slide block 44. The wedge 46 extends through a suitable opening 49 in the slide 34 and is drawn downwardly by means of a pitman 50 operated by an eccentric 51. Any suitable means, such as a spring, may be provided for giving the slide block 44.- its return relative movement.

Assuming the blank to be positioned in its holder, upon advance of the pushing element, the head of the blank is forced through the cutting die 12, pusher block 36 and pusher rod 41 operating as a unit at this time and holder 15 withdrawing as the blade advances. During this movement of the blank, the die cuts "the metal of the head away, starting at the bottom of the head and working toward the top, the cut away metal forming a V tal-li e flange around the blank head. t will be noted that the front faceof the cutting die 12 falls away fromthe center (see Fig. 2) and the pusher block 36 has a' central boss 52, dished to accord with the rounded top of the blank. Consequently there is a space 53 for the waste flange between the die and the pusher block. As the cutting continues, the cut-away flange eventually reaches the to of the head, as shown at 103, Fig. 9. At this time, the pusher block 36 firmly pinches or grasps the waste flange between itself and the front face of die 12 and the differential pusher bar 41 now makes its relative IHOVQ' ment to continue the pushin stroke; Under this continued advance 0 the blank the waste flange, while firmly held,'is severed from the head, thus ompleting the cutting of the facets (see Fi'gfii).

The invention includes a planishing die and means whereby the lanishin operation -is eflectively lubricated. though capable of various constructions, ashere illustrated, back of the cuttin die is a lanishingdie54als0carriedby ediebl 13.

III

a i 59of luh aaaasao 3 die 54 has an hexagonal return stroke but the holder 15 continues esigned to planish the cut. backward to'carry the blank against the roughnes, in 18, thereb to eject the blank from the the waste lder. The older 15 is then returned to ange was severed. position and the pushing element To provide suitable lubrication, as here returns to initial position, the arts being illustrated as an example, at the back of read for another cycle. Itwi be undervthe cutting die 12 is a mm 55 provided with that the above described movements a groove 56 extending from the circumare, in many respects, more or-lesssim'ultaference of the die to its bore. Opposite this neous.

ve, the front face of the plamshing die With the construction described the blank as a similar groove 57. These two grooves is cut, planished and ejected by a one-way, form a channel .which communi continuous movement. By die-cutting the through a bore 58 in the die block 13, with blank so as to form a wasteflange at the This lanishinfi bore Fig. 6)

facets, thereby to remove any articularly at the point where rlcating system. waste flange at the time it is severed, and by any suitable force feed or otherextremity of the cut facets, by pinching this Means is provided for ejecting the cut and planishing the cut facets, the metal of 'the planished blanks and in constructions emfacets is not torn and the final surfaces have J bodying the invention to the best advantage the smooth, clean finish that is commerthe blank is moved against a stationary cially desirable, and this is accomplished ejecting abutmentiby the same one-way conwithout subjecting the cap-screws to the and er bar.

tinuous movement tha carrim it through action of a milling machine. the cutting and pl dies. As here What I-cla1m 1s: illustrated as an example, the end of rod 1. In a machine of the cla$ described,

' 18 serves as a stationary ejectingabutment. and in combination a. cuttin die, a holder After the blank head has passed through the. for a headed blank, means or forcing the planishing die, the holder 1516 continues blank head through the die including a reits backward stroke, the blank being carried ciprocatin lpusher bar, and a spring-pressed against the end 10f rod 18 which causes the pm carrie y thepusher bar and serving as blank to be ejected from the holder as the a knock out to prevent the blank from follatter moves back, The ejected blank drops lowing the pusher bar when the'latter is down. the slanting runway 60 to any smtwithdrawn. r v able collecting element. a '2. In; a machine of the class described, Meantime, the pusher bar 41 has started and in combination a stationary cutting die its return stroke. As the parts operate in and planishing die having aligning bores, a a hea lubricant'there is a strong suction channel for supplying lubricant to the bores u n t e return movement of the usher. of said dies, a tubular blank holder to the o prevent this suction from displacing the rear of the dies, a'pusher bar, means for adblank from the holder, the pin 42 is provancing the pusher bar toward and into the vided. As the pusher bar starts to withdies to push the blank through the dies,-and draw the pin 42 is forced outward by its thereafter withdrawing the same, and a spring and thus serves as a knock-out to spring-pressed knockout pin carried by the prevent the blank from following the pushpousher bar for preventing the blank from N llowing the pusher bar when the latter is .The operation of the aplparatus will be withdrawn. clear fromthe fore ing. 0 sum itilp, howa 3. In a machine of the cla$ described, and ever, the pushing e ement being wi drawn in combination, ahexagon cutting die, a twoand the holder advanced (Fig. 2) the grippart non-cutting ushmg device comprisin per 29 takes a blank from slide 31 and a pushing block lihving a borecoaxial wit owers it to a position opposite the die 12. the bore of the" die and asupplemental pusher The prstushing element now advances as a unit movable in the bore of the pusher block and pushes the blank into the die and having a diameter to permit passage through then forces the blank head through the the bore of the cutting cutting die 12, holder 15 be' the blank 1% advanced. The ange of waste, rounding the bore of the latter, and means cut away metal, as it reaches the topf the for (a)' advancing the pushin device as a blank head, is grasped or pinched. ween unit toward the die to push t 0 head of a the pusher block 36 and the face of the blank through the die a sufiicient distance to p die, a hexa nal boss withdrawn as on the front face of the pusher lock surdie.12'and while so grasped, is severed by the die as the pusher bar 41 makes its differential movement and forces the blank head onward. Continued movement of thepusher bar 41 forces the blank head through die 54 which planishes the cut such endof the head, (b) holding the pusher block in its advanced position to clamp the wasteburrbetweentheboss andtheface of TEe-pushingelement now. startsits the die, and (c) advancing the supplemental 1:0

pushcr alone while the pusher block is so held to continue the movement of the blank head through the die and cause severing of the waste burr while it is so clamped.

' 4. In a machine of the class described, and in combination, a hexagon cutting die, a planishing die rearward of the cutting die, a two-part non-cutting pushing device contprising a pushing block having a bore coaxial with the bore of the die and a supplemental pusher movable in the bore of the pusher block and having a diameter to permit passage through the bore of the cutting die, a hexagonal boss on the front face of the pusher block surrounding the bore of the latter, and means for (a) advancing the pushing device as a unit toward the die to push the head of a blank through the die a sufiieient distance to cause cuttin of the facets up to a point adjacent the trailing end of the head, whereby av burr of waste metal is formed adjacent such end of the head, (b) holding the pusher block in its advanced position to clamp the waste burr between the boss and the face of the die, and (c) advancing the supplemental pusher alone while the pusher block is so held to continue the movement of the blank head through the die and. cause severing of the waste burr while it is so clamped and thereafter through the planishing die.

5. In a machine of the class described,

and in combination, a hexagon cutting die,

and non-cutting means for (a) forcing the head of a blank through said cutting die a suflicient distance to cause cuttin of the facets up to a point adjacent the trailing end of the head, whereby a burr of waste metal is formed adjacent such end of the head, (b) clamping said .waste burr against the, face of the die, and (c) continuing the forcing of the head .of the blank through the die in the same direction to sever the waste burr while the same is so clamped.

6. In a machine of the class described, and

die in the same direction to sever the waste burr while the same is so clamped and thereafter through the planishing die.

7. In combination, two metal-working dies arranged in tandem and having coaxial bores, the opposing faces of said dies having a channel formed therebetween leading to the bores 'of the dies and adapted for communication with a lubricating system.

8. In combination, two metal-working dies having bores, one die having a groove in its rear face, the other die having a groove in its front face, each of said grooves communicating with the respective die bore, the grooves being so arranged that when the dies are assembled in tandem with their bores eoaxially arranged said grooves provide a channel for the delivery of a lubricant to said bores.

9. In a machine of the class described, and in combination, a die block two metalworkin dies mounted in tandem in said die bloc with their bores coaxial, the opposing faces of said dies having a channel formed therebetween leading to said bores, the die block having a passagewa communicating with said channel, where y a lubricant may be delivered to said bores, and means for forcing a blank through the said bores.

In testimony whereof, I have hereunto set my hand.

VINCENT HUSVAR. 

